Light emitting device

ABSTRACT

It is an object of the present invention to prevent an insulating film from peeling in a section where the insulating film is adjacent to a sealing region. Over a first substrate  104,  a pixel portion  100  provided with a light emitting element, a source driver  101,  a gate driver  102,  and a sealing region  103  are provided. A light emitting element is sealed between the first substrate  104  and a second substrate  110  by a sealant  108.  An insulating film  107  serves as a partition wall of the light emitting element. An end portion of the insulating film  107  which is adjacent to the sealing region  103  does not overlap with a step formed by a side surface and an upper surface of a conductive film  106  which serves as a wiring.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a light emitting device having a lightemitting element.

2. Description of the Related Art

In recent years, the development of display devices that use a lightemitting element which utilizes the EL phenomenon of light emittingmaterial (hereinafter referred to as an ‘electroluminescent element’ oran ‘EL element’) in a pixel (hereinafter referred to as‘electroluminescent display devices’ or ‘EL display devices’) has madeprogress.

Light emitting materials used in EL elements include inorganic lightemitting materials and organic light emitting materials. Organic lightemitting materials have the advantage of low driving voltage. However,organic EL elements that use organic material are easily affected bymoisture and oxygen, compared with inorganic EL elements. Therefore, anorganic EL display device structure in which an EL element is sealedbetween a pair of substrates such that water and oxygen does notpenetrate from outside is known.

FIGS. 10A and 10B show a conventional EL display device. FIGS. 10A and10B are a cross-section of a portion in which a sealant is provided.Reference numerals 11 and 12 indicate substrates. The substrates inFIGS. 10A and 10B are provided with EL elements, although they are notshown in the drawings. The substrate 12 is a sealing substrate forsealing the EL element. The substrate 11 has a sealing region 14 inwhich the sealant 13 is provided. The sealing substrate 12 is fixed tothe substrate 11 by the sealant 13. The space between the substrate 11and the substrate 12 is filled with a filler material 15, such as resin.

Reference numeral 16 indicates a lead wiring, such as a power sourceline, a signal line, or the like, which leads from a source driver, agate driver, an FPC terminal, or the like. Reference numerals 17 and 18indicate insulating films. The insulating film 18 is for separating alight emitting layer of an EL element in a pixel from the light emittinglayer of an EL element in another pixel in a pixel portion, and iscalled an embankment, a bank, or a partition wall. Here, the insulatingfilm 18 is referred to as a partition wall. An opening is formed in asection that corresponds to the sealing region of the partition wall 18.The opening is where the sealant 13 is to be provided.

SUMMARY OF THE INVENTION

By providing an opening in the partition wall 18 in this manner, manysections can be formed in which an upper surface of the wiring 16overlaps with an end portion of the partition wall 18, as shown in FIG.10A (the sections surrounded by dotted lines), and many sections can beformed in which a side surface of the wiring 16 is in alignment with anend portion of the partition wall 18, as shown in FIG. 10B (the sectionssurrounded by dotted lines). It has come to be known that the endportion of the partition wall 18 peels off easily in these sections. Anend portion of the partition wall 18 that has come off the substrate 11becomes a contaminant, and there is a risk that it may enter the pixelportion. If such an insulating film is attached to a light emittingelement, poor quality display results.

One cause of the partition wall 18 peeling is that when organic resin isused for the partition wall 18, the partition wall 18 has poor adhesionto a conductive film which is used as the wiring 16. In particular, thepartition wall 18 has particularly poor adhesion to a wiring with atitanium (Ti) surface.

In the case of forming the partition wall 18 with organic resin, afterproviding an opening in the sealing region 14, there is a baking processto remove moisture. However, since this baking process contracts thepartition wall 18, when an end portion of the partition wall 18 overlapswith a step portion of the wiring 16, at that section, the partitionwall 18 may be cut off or the like, and easily peels. This is becausethe end portion of the partition wall 18 becomes thin as a result of theopening being provided in the sealing region 14.

An object of the present invention is to prevent an end portion of apartition wall which is adjacent to a sealing region from peeling off.

A light emitting device of the present invention includes a firstsubstrate and a second substrate. The first substrate includes a pixelportion having a light emitting element, and a sealing region in which asealant is formed in a section surrounding the pixel portion. The secondsubstrate is fixed to the first substrate by the sealant.

In the present invention, an EL element can be used as a light emittingelement. As an EL element, an inorganic EL element, an organic ELelement, or an EL element which uses a light emitting material which isa mixture of an inorganic light emitting material and an organic lightemitting material can be used.

As examples of a light emitting device of the present invention, an ELdisplay device, a lighting device, and the like can be given. The ELdisplay device may be active or passive. Further, as an example of alighting device, a backlight of a liquid crystal panel can be given.

In order to achieve the above-mentioned object, in the presentinvention, an end portion of a partition wall that is adjacent to asealing region does not overlap with a step between a base film and aconductive film such as a wiring of a driver circuit or a lead wiring. Afirst substrate includes a first insulating film, a conductive film overthe first insulating film, and a second insulating film over theconductive film. A section of the second insulating film where a sealingregion is to be formed is removed, and a sealant is provided in thesealing region. An end portion of the second insulating film which isadjacent to the sealant does not overlap with a step made by a sidesurface and an upper surface of the conductive film.

The second insulating film which serves as the partition wall is a filmformed of an organic resin, for example, acrylic, polyimide-polyamide,or polyimideamide. Further, a film formed by applying an insulating filmmaterial that has been dissolved in an organic solvent, then conductingheat treatment—a so-called coated silicon oxide film (also called a‘spin on glass’ film, referred to as an ‘SOG’ film below)—can be used asthe second insulating film. For example, a film formed of a material inwhich a siloxane bond is formed by baking, such as a siloxane polymer,can be used.

One feature of the present invention is that peeling of a partition wallis prevented by forming an insulating film, which adheres well to aninsulating film which forms the partition wall, between a wiring and theinsulating film which forms the partition wall, so that the wiring andthe insulating film which forms the partition wall are not in directcontact. That is, on a first substrate are formed a first insulatingfilm, a conductive film over the first insulating film, a secondinsulating film over the conductive film, and a third insulating filmover the second insulating film. A section of the third insulating filmwhere a sealing region is to be formed is removed, and a sealant isprovided in the sealing region. The second insulating film is formed ofinorganic material, and the third insulating film is provided in such amanner that it is not in contact with the conductive film.

As the second insulating film formed of inorganic material, any one of asilicon oxide film, a silicon nitride film, and a silicon oxynitridefilm can be used, or a plurality of those films can be layered.

Further, the third insulating film which serves as a partition wall isformed of an organic resin, for example, acrylic, polyimide-polyamide,or polyimideamide. Further, as the second insulating film, an SOG film,such as a film formed of a material in which a siloxane bond is formedby baking, for example, a siloxane polymer, can also be used.

One feature of the present invention is that peeling of a partition wallis prevented by using an inorganic film that adheres well to a wiring asa material for the partition wall. A first substrate includes a firstinsulating film, a conductive film which is over the first insulatingfilm, and a second insulating film formed of inorganic material which isover the conductive film. A section of the second insulating film wherea sealing region is to be formed is removed, and a sealant is providedin the sealing region.

As the second insulating film, which serves as the partition wall, anyone of a silicon oxide film, a silicon nitride film, and a siliconoxynitride film is used, or a plurality of such films is layered.

The conductive film, provided below the insulating film serving as thepartition wall, serves as a wiring or as an electrode. For theconductive film, a film formed of aluminum, titanium, molybdenum, ortungsten, or of a material chosen from among compounds of such metalscan be used. Alternatively, a layered plurality of such films can beused.

According to the present invention, an end portion of an insulating filmwhich is adjacent to a sealant can be prevented from peeling off.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B are explanatory diagrams of Embodiment Mode 1.

FIGS. 2A and 2B are explanatory diagrams of Embodiment Mode 1.

FIGS. 3A and 3B are explanatory diagrams of Embodiment Mode 2.

FIGS. 4A and 4B are explanatory diagrams of Embodiment Mode 2.

FIGS. 5A and 5B are explanatory diagrams of Embodiment Mode 3.

FIGS. 6A and 6B show cross-sections of a light emitting device (an ELdisplay device) of Embodiment 1.

FIG. 7 shows a pixel circuit of Embodiment 2.

FIGS. 8A and 8B show a pixel circuit of Embodiment 2.

FIGS. 9A to 9F show examples of applications of the present invention toelectronic devices of Embodiment 3.

FIGS. 10A and 10B illustrate examples of conventional art.

DETAILED DESCRIPTION OF THE INVENTION Embodiment Modes

The present invention will be described below by way of embodimentmodes, with reference to the accompanying drawings. In the drawings,parts which are the same or which have similar functions are denoted bythe same reference numerals, and repetitious explanation thereof isomitted. The invention can be carried out in many different modes, andthose skilled in the art will appreciate that a variety of modificationscan be made to the embodiment modes without departing from the spiritand scope of the invention. Accordingly, the present invention is not tobe construed as being limited to the embodiment modes described below.

Embodiment Mode 1

FIG. 1A is a top view of a display device. FIG. 1B is a cross-sectiontaken along line X to X′ of FIG. 1A. As shown in FIG. 1A, the displaydevice includes a pixel portion 100 having a light emitting element, asource driver 101 and a gate driver 102 as driver circuit portions, anda sealing region 103 on the periphery of the pixel portion 100, whichsurrounds the pixel portion 100. The sealing region 103 is a regionwhere a sealant is provided for the purpose of sealing. A structure inwhich the source driver 101 and the gate driver 102 are not providedover a first substrate 104 is also included in this embodiment mode.

An insulating film 105 is provided over the first substrate 104. As theinsulating film 105, for example, a single layer film of inorganicmaterial, such as a silicon oxide film, a silicon nitride film, or asilicon oxynitride film is used, or a layered film including a pluralityof one or more of such films can be used. For example, a three-layersilicon oxynitride film in which the composition ratio of each layerdiffers can be used.

Over the insulating film 105, a conductive film 106 which serves aswirings or as electrodes is provided. The conductive film 106 is formedof metal or a metal compound, and is a single layer film or a layeredfilm. For example, a film formed of a layer of titanium (Ti), a layer ofaluminum (Al), and a layer of titanium (Ti) can be used.

An insulating film 107 formed of organic material is formed over theconductive film 106. The insulating film 107 serves as a partition wall.As examples of the insulating film 107, an organic resin such aspolyimide or acrylic can be given. The insulating film 107 formed oforganic material has good adhesion to the insulating film 105; however,it has poor adhesion to the conductive film 106.

A section of the insulating film 107 formed of organic material wherethe sealing region 103 which surrounds the pixel portion 100 is to beformed is selectively removed. The sealing region 103 is formed to asize which is ideal for the size and type of the display device andwhich is in accordance with processing rules. The sealing region 103 isformed to a size which is sufficient for the formation of the sealant108.

The second substrate 110 is a sealing substrate, and is fixed to thefirst substrate 104 by the sealant 108, which is provided in the sealingregion 103. A sealed space between the first substrate 104 and thesecond substrate 110 is filled with a filler material 109, such as anorganic resin.

In the sealing region 103, the insulating film 107 formed of organicmaterial is removed. An end portion of the insulating film 107 oforganic material that is adjacent to the sealing region is not incontact with a side surface of the conductive film 106. As shown in FIG.1B, the end portion of the insulating film 107 is formed over theinsulating film 105 between conductive films 106. In other words, theend portion of the insulating film 107 is only in contact with an uppersurface of the insulating film 105, and not with a side surface of theconductive film 106.

In this embodiment mode, the end portion of the insulating film 107formed of organic material is disposed such that it is not in contactwith a side surface of the conductive film 106. Thus, the end portion ofthe insulating film 107 formed of organic material is prevented frompeeling off.

The positional relationship of the conductive film 106 and theinsulating film 107 will be explained with reference to FIGS. 2A and 2B.FIG. 2A is an enlarged version of the region indicated by ‘a’ in FIG.1A. FIG. 2B is a drawing which illustrates the end portion of theinsulating film 107. In a most preferable mode of this embodiment mode,none of the end portion of the insulating film 107 is over theconductive film 106. In this embodiment mode, the end portion of theinsulating film 107 does not overlap with at least a step formed by aside surface and a top surface of the conductive film 106. The filmthickness of the end portion of the insulating film 107 is very thin, soby ensuring the end portion does not overlap with the step of theconductive film 106, the end portion can be prevented from peeling off.

The end portion of the insulating film 107 will be described withreference to FIG. 2B. In this embodiment mode, the end portion of theinsulating film 107 refers to a region 200 whose width ‘W’ from theboundary of the sealing region (i.e., from a tip of the insulating film107 which is in contact with the sealant 108) is 0.5 μm. Alternatively,the end portion of the insulating film 107 refers to a region 200 whosefilm thickness ‘d’ from the boundary of the sealing region 103 is 42 nmor less. Further, from the standpoint of preventing peeling from the endportion, it is more preferable to consider the end portion of theinsulating film to be a region whose film thickness ‘d’ from theboundary of the sealing region 103 is 50 nm or less. In this embodimentmode, the end portion of the insulating film 107 is a region 200determined by either the width ‘W’ or the film thickness ‘d’ from thetip of the insulating film 107, as explained above. The term ‘endportion of the insulating film 107’ refers to the same region in theother embodiment modes.

In this embodiment mode, the region 200, which is the end portion of theinsulating film 107, is provided such that it does not overlap with thestep of the conductive film 106. In other words, the entire end portionof the insulating film 107 is provided such that it is positioned on anupper surface of the conductive film 106, or on an upper surface of theinsulating film 105, which is the base section of the conductive film106. For example, as shown in FIG. 2A, an end portion 200 a of theinsulating film 107 is formed on the insulating film 105, or an endportion 200 b of the insulating film 107 is formed on the conductivefilm 106. The end portion 200 a and the end portion 200 b are shownrepresentatively. However, in this embodiment mode, in the section ofthe insulating film 107 which is in contact with the sealing section103, the region 200 (i.e., the end portion of the insulating film 107)is disposed only on an upper surface of the insulating film 105, in thesame manner as the end portion 200 a, or only on an upper surface of theconductive film 106, in the same manner as the end portion 200 b.

Embodiment Mode 2

In this embodiment mode, a method of preventing an end portion of aninsulating film from peeling off by ensuring that a wiring and apartition wall are not in direct contact is explained. FIG. 3A is a topview of a display device. FIG. 3B shows a cross-section taken along lineY to Y′ of FIG. 3A. In this embodiment mode, a surface of the sealingregion 103 is covered by an insulating film 300 formed of inorganicmaterial.

In this embodiment mode, an insulating film 300 formed of inorganicmaterial is provided over the entire substrate 104, covering aconductive film 106. As the insulating film 300 formed of inorganicmaterial, for example, a silicon oxide film, a silicon nitride film, asilicon oxynitride film, or the like, can be used. The insulating film300, which is formed of an inorganic material which has good adhesion toorganic material, is interposed between the conductive film 106 and theinsulating film 107 formed of organic material. Therefore, even if anend portion of the conductive film 106 overlaps with an end portion ofthe insulating film 107, as shown in FIG. 4A, or is in alignment with anend portion of the insulating film 107, as shown in FIG. 4B, peeling ofthe insulating film 107 formed of organic material can be prevented.Accordingly, in this embodiment mode, the degree of freedom of thelayout of the conductive film 106 and the sealing region 103 isincreased.

Embodiment Mode 3

In this embodiment mode, a method of preventing an end portion of aninsulating film from peeling off by changing the material used for theinsulating film, which serves as a partition wall, is explained.

FIG. 5A is a top view of a display device. FIG. 5B shows a cross-sectiontaken along line Z to Z′ of FIG. 5A.

In this embodiment mode, instead of an insulating film 107 formed oforganic material, an insulating film 500 formed of inorganic material isprovided. As shown in FIG. 5B, an end portion of the insulating film 500is provided between conductive films 106 which are adjacent to eachother. For the insulating film 500, a single layer film of siliconoxide, silicon nitride, or silicon oxynitride can be used, or a layeredfilm including such single layer films can be used.

By forming the insulating film 500 of inorganic material, its adhesionwith the conductive film 106 is improved. Accordingly, the degree offreedom of the layout of the conductive film 106 is increased. An endportion of the conductive film 106 may overlap with an end portion ofthe insulating film 500, or it may be in alignment with an end portionof the insulating film 500. Since the insulating film 500 formed ofinorganic material has good adhesion to the conductive film 106, peelingof the inorganic insulating film 500 formed of inorganic material can beprevented. Further, the degree of freedom of the layout of theconductive film 106 and the layout of the sealing region 103 isincreased.

Embodiment 1

This embodiment is an example of the application of the presentinvention to an EL display device. This embodiment will be explainedusing FIGS. 6A and 6B. FIG. 6A is a top view of a panel in which TFTsand light emitting elements formed over a first substrate are sealedbetween the first substrate and a second substrate by a sealant. FIG. 6Bis a cross-section corresponding to line A to A′ of FIG. 6A.

A pixel portion 4002, a source driver 4003, and a gate driver 4004 areprovided over the first substrate 4001, and the sealant 4005 is providedso as to surround the pixel portion 4002. Further, over the pixelportion 4002, the second substrate 4006 is provided, with the sealant4005 interposed therebetween. The pixel portion 4002, the source driver4003, the gate driver 4004, and the filler material 4007 are sealed inby the first substrate 4001, the sealant 4005, and the second substrate4006.

As the first substrate 4001 and the second substrate 4006, glass, metal(representatively, stainless steel), ceramics, or plastic can be used.As a plastic, an FRP (fiberglass reinforced plastic) substrate, a PVF(polyvinyl fluoride) film, a Mylar film, a polyester film, or an acrylicresin film can be used. Further, a sheet with a structure in whichaluminum foil is interposed between PVF films or Mylar films or betweena PVF film and a Mylar film can also be used. The substrate positionedwhere the light from the light emitting element 4011 is to pass throughshould have a light transmitting property. For such a substrate, amaterial having a light transmitting property is used. For example, aglass substrate, a plastic substrate, a polyester film, or an acrylicfilm is used.

As the filler material 4007, besides an inert gas such as nitrogen orargon, an ultraviolet curing resin or a thermoset resin can be used. PVC(polyvinyl chloride), acrylic, polyimide, an epoxy resin, a siliconresin, PVB (polyvinyl butyral), or EVA (ethylene vinyl acetate) can alsobe used. In this embodiment, nitrogen is used as the filler material.

The pixel portion 4002, the source driver 4003, and the gate driver4004, which are provided over the first substrate 4001, include aplurality of thin film transistors (TFTs). In FIG. 6B, a TFT 4008included in the source driver 4003 and a TFT 4009 included in the pixelportion 4002 are shown by way of example.

Reference numeral 4011 corresponds to a light emitting element. A partof a wiring 4017 which is connected to a drain of the TFT 4009 serves asa first electrode of the light emitting element 4011. A transparentconductive film 4012 serves as a second electrode of the light emittingelement 4011. Between the first electrode and the second electrode is alight emitting layer 4013 which includes a light emitting material. Notethat the structure of the light emitting element 4011 is not limited tothe structure shown in this embodiment. The structure of the lightemitting element 4011 can be changed as appropriate, in accordance withthe direction in which light from the light emitting element 4011passes, as mentioned above, or the polarity of the TFT 4009, forexample. Light from the light emitting element 4011 may go toward thefirst substrate 4001 side, the second substrate 4006 side, or towardboth the first substrate 4001 side and the second substrate 4006 side.

Various signals and voltages provided to the source driver 4003, thegate driver 4004 or the pixel portion 4002 are not shown in thecross-section of FIG. 6B. However, they are supplied from an FPCterminal 4016 through power source lines 4014 and 4015, which lead outfrom the FPC terminal 4016.

In this embodiment, the FPC terminal 4016 is formed from the sameconductive film as the first electrode of the light emitting element4011. Further, the power source line 4014 is formed from the sameconductive film as the wiring 4017. Moreover, the power source line 4015is formed from the same conductive film as the gate of the TFT 4009 andthe gate of the TFT 4008.

The FPC terminal 4016 is electrically connected to a terminal includedin an FPC 4018 by an anisotropic conductive film 4019.

For an insulating film 4022, a single layer film or a layered film of anorganic resin material such as polyimide, acrylic, or polyimideamide canbe used. For an insulating film 4021, a single layer film or a layeredfilm formed of an inorganic material, such as a silicon oxide film, asilicon nitride film, or a silicon oxynitride film, can be used.

The insulating film 4022 is an insulating film which separates the lightemitting layer 4013 of the light emitting element 4011 in one pixel fromthe light emitting layer 4013 of the light emitting element 4011 inanother pixel, and is formed over an entire surface of the firstsubstrate 4001. Openings are formed in the insulating film 4022 byselectively removing a region where the light emitting element 4011 isformed and a sealing region 4020 by etching. As shown in FIG. 6B, in thesealing region 4020, an end portion of a conductive film, typified bythe power source line 4014, does not overlap with or align with an endportion of the insulating film 4022. As a result, since an end portionof the insulating film 4022 is in contact with the insulating film 4021,which is formed with an inorganic material which has good adhesion tothe insulating film 4022, peeling from an end portion of the insulatingfilm 4022 formed of organic material can be prevented.

Embodiment 2

In this embodiment, a circuit of the pixel portion in Embodiment 1 willbe explained. Note that the pixel circuit of the present invention isnot limited to the circuit described in this embodiment.

FIG. 7 is an example of an equivalent circuit diagram of a pixel. Thepixel includes a signal line 6114, a power source line 6115, a scan line6116, a light emitting element 6113, transistors 6110 and 6111, and acapacitor element 6112. A video signal is input to the signal line 6114by the source driver. According to a selection signal input to the scanline 6116, the transistor 6110 can control the supply of the potentialof the video signal to a gate of the transistor 6111. The transistor6111 can control the supply of current to the light emitting element6113, according to the potential of the video signal. The capacitorelement 6112 can store the gate-source voltage of the transistor 6111.Note that in FIG. 7, the capacitor element 6112 is illustrated, but inthe case where the gate capacitance of the transistor 6111 or otherparasitic capacitance is enough that the gate-source voltage of thetransistor 6111 can be stored, the capacitor element 6112 does not haveto be provided.

FIG. 8A is an equivalent circuit diagram showing the pixel of FIG. 7,with a transistor 6118 and a scan line 6119 additionally provided. Thetransistor 6118 can make the potentials of the gate and the source ofthe transistor 6111 equal, and forcibly create a state in which currentdoes not flow to the light emitting element 6113. Therefore, the lengthof a subframe period can be made shorter than the time it takes forvideo signals to be input to all the pixels. Accordingly, this issuitable for conducting display with a high total number of gradationswhile suppressing drive frequency.

FIG. 8B is an equivalent circuit diagram of the pixel shown in FIG. 8A,with a transistor 6125 and a wiring 6126 additionally provided. Theelectric potential of a gate of the transistor 6125 is fixed by thewiring 6126. Further, the transistor 6111 and the transistor 6125 areconnected in series between the power source line 6115 and the lightemitting element 6113. Therefore, in the pixel shown in FIG. 8B, theamount of current supplied to the light emitting element 6113 iscontrolled by the transistor 6125, and the transistor 6111 can controlwhether or not the current is supplied to the light emitting element6113.

Embodiment 3

An EL display device to which the present invention is applied issuitable for use in the display portion of a battery-powered electronicdevice, or for use as the display device of a large screen, or for usein the display portion of an electronic device. For example, an ELdisplay device to which the present invention is applied may be appliedto a television device (for example, a television or a televisionreceiver), a camera, such as digital camera or a digital video camera, aportable telephone device (for example, a portable telephone), aportable information terminal, such as a PDA, a portable game machine, amonitor, a computer, a sound reproduction device such as a car audiodevice, an image reproduction device equipped with a recording medium,such as a home game machine, or the like. Some specific examples ofthese will be explained with reference to FIGS. 9A to 9F.

The portable information terminal device shown in FIG. 9A includes amain body 9201, a display portion 9202, and the like. A display deviceof the present invention can be applied to the display portion 9202.Accordingly, a portable information terminal device in which peeling ofa partition wall is prevented can be provided.

The digital video camera shown in FIG. 9B includes a display portion9701, a display portion 9702, and the like. A display device of thepresent invention can be applied to the display portion 9701.Accordingly, a digital video camera in which peeling of a partition wallis prevented can be provided.

The portable telephone shown in FIG. 9C includes a main body 9101, adisplay portion 9102, and the like. A display device of the presentinvention can be applied to the display portion 9102. Accordingly, aportable telephone in which peeling of a partition wall is prevented canbe provided.

The portable television device shown in FIG. 9D includes a main body9301, a display portion 9302, and the like. A display device of thepresent invention can be applied to the display portion 9302.Accordingly, a portable television device in which peeling of apartition wall is prevented can be provided. Further, a display deviceof the present invention can be applied to a wide range of televisiondevices, from small television devices mounted on a portable terminal,such as a portable telephone, to medium-sized portable televisiondevices and large television devices (for examples, those 40 inches andabove).

The portable computer shown in FIG. 9E includes a main body 9401, adisplay portion 9402, and the like. A display device of the presentinvention can be applied to the display portion 9402. Accordingly, aportable computer in which peeling of a partition wall is prevented canbe provided.

The television device shown in FIG. 9F includes a main body 9501, adisplay portion 9502, and the like. A display device of the presentinvention can be applied to the display portion 9502. Accordingly, atelevision device in which peeling of a partition wall is prevented canbe provided.

The present application is based on Japanese Priority application No.2006-010197, filed on Jan. 18, 2006 with the Japanese Patent Office, theentire contents of which are hereby incorporated by reference.

What is claimed is:
 1. A display device comprising: a first substratecomprising a pixel portion and a sealing region; a sealant formed in thesealing region which surrounds the pixel portion; a second substratefixed to the first substrate by the sealant; a transistor over the firstsubstrate; a light emitting element over the first substrate; aconductive film over the first substrate and in contact with thesealant; a first insulating film over an edge portion of an electrode ofthe light emitting element, and wherein a light emitting layer of thelight emitting element is positioned over the first insulating film; asecond insulating film over the first substrate; a first gate driverover the first substrate; and a second gate driver over the firstsubstrate, wherein the first insulating film is positioned in the pixelportion, wherein the second insulating film is positioned in a region,wherein the sealing region is positioned between the region and thepixel portion, wherein the first insulating film and the secondinsulating film are formed of the same material, wherein the firstinsulating film and the second insulating film comprise organic resin,wherein the conductive film and a source electrode and a drain electrodeof the transistor are formed of the same material, and wherein thesecond substrate overlaps with a part of the second insulating film.